The objectives of the proposed research concerning activation and detoxification of toxic and carcinogenic haloalkenes are enumerated below: 1) Determination of the alkylating agents involved in the covalent binding of vinyl chloride, vinylidene chloride, trichloroethylene, vinyl bromide and acrylonitrile to protein and nucleic acids, 2) elucidation of the role of epoxide hydratase in the metabolism of vinyl halides in vivo and in vitro, 3) immunohistochemical localization of epoxide hydratase in liver and lung, 4) examination of vinyl halide metablism in the lung in vitro, 5) determination of the mechanism of cytochrome P-450 heme destruction that occurs during haloalkene metabolism, and 6) examination of DNA-chromatin protein crosslinking by metabolites of haloalkenes.